diff --git a/src/include/pmt.h b/src/include/pmt.h
index 2142c97..a7d871e 100644
--- a/src/include/pmt.h
+++ b/src/include/pmt.h
@@ -21,7 +21,7 @@ extern "C" {
 #endif
 
 /* check compiler. only NDK supported */
-#if !defined(__NDK__)
+#ifndef __NDK__
     #error "compilation can only be done with android NDK"
 #endif